Developments in library cooperation in New York State as a result of library pilot projects organized under Chapter 787 of the Laws of 1978 are described, the background of the pilot projects is summarized, and major accomplishments in resource sharing and in increasing public access to library materials as a result of the projects are outlined. The activities undertaken and services provided by two major regional library networks that are discussed include INTERSHARE, which serves the New York City area, and the Rochester Area Resources Exchange (RARE). A review of the accomplishments of school library system pilot projects throughout New York State is followed by a consideration of school library systems from a national perspective, and a description and assessment of the library-oriented activities of the State Department of Education. Detailed profiles of the INTERSHARE and RARE projects, as well as profiles of five other regional projects, are also provided. A set of 13 tables containing data on various aspects of statewide participation in library pilot projects accompanies the text. Among the five appendices to the report are excerpts from Chapter 787 of the Laws of 1978, and a historical summary and list of library pilot projects in New York State. (JL)